Hundreds of pupils with special needs have been waiting too long for proper support, with the council consistently missing its 20-week target for processing vital new care plans.
New figures published by the Department for Education (DfE) show three quarters of children issued with a new education, health and care plan (EHCP) last year had to wait too long for appropriate support.
EHCPs are care plans tailored to children and young people with the most complex needs, and should be drawn up by the local authority in 20 weeks or less.
But in 2018, Suffolk County Council (SCC) exceeded the legal time limit for processing 75% of all successful applications, excluding exception cases.
This is a huge increase on the number of missed targets in 2017 - when roughly half of all children had their plans issued on time.
The council has admitted the timeliness of its assessment process is "currently a lot lower" than it would like to see, and it is "working very hard" to make fast improvements.
It added that "significant progress" has been made to improve the completion rate in last few months - with an average of 42.5% of EHCPs currently finalised within the set timeframe.
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Suffolk's record does not compare favourably to the East of England as a whole - where last year 60.9% of children received their care plans within 20 weeks.
The time frame is laid out in the SEND code of practice, compiled by the Department for Education and Department of Health.
The code states: "The whole process of EHC needs assessment and EHC plan development, from the point when an assessment is requested (or a child or young person is brought to the local authority's attention) until the final EHC plan is issued, must take no more than 20 weeks (subject to exemptions)."
'It's all extremely stressful and frustrating'
Speaking on behalf of Suffolk support group Parents and Carers Together (PACT), co-founder and trustee Rebecca Jasper said the current process "is not set up around the best interests of the child" and there should be "zero EHCPs exceeding the 20 week timescale" in Suffolk.
"We are not surprised to hear that 75% of EHCPs were not finalised within the 20 week legal timeframe," she said.
"This ties in with around 80% of our own (PACT) parents responding that their EHCPs were over the 20 week timeframe.
"We understand that staff changes and restructuring may have impacted on timeliness, but this is no defence when you consider there are real children and families waiting patiently for their EHCPs to be provided.
"In reality this has quite often taken years of fighting for the rights of a child to be assessed - let alone the many appointments, phone calls, research and then awaiting the final results, which is all extremely stressful and frustrating."
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Annie Clements, founder of Suffolk-based support service Autism & ADHD, added: "It is very frustrating if the council missed its 20-week target for EHCPs in 75% of cases last year.
"This causes such huge stress for families and delays them getting support in school and from the health service. It can also lead them to miss deadlines to apply for specialist placements that may meet that child's needs.
"This doesn't just impact on their education but also their home life, causing additional problems.
"This delay needs to be addressed as soon as possible to minimise stress for those concerned and ultimately reduce costs, as needs would be supported more quickly and wouldn't escalate."
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Council response
Chris Chambers, deputy cabinet member for education said: "We accept that the timeliness of our assessment process is currently a lot lower than we want to see. We are working very hard, taking significant action and steps to improve this as quickly as possible.
"Significant progress has been made to improve the completion rate in the last four months. Whilst this retrospective report for 2018/19 is showing a 28%* completion rate for EHC Plans within the 20-week timescale, we are currently seeing an average of 42.5% of EHC Plans completed within the set timeframe and we continue pushing towards the national completion rate target.
"Between April 2018 and March 2019 Suffolk County Council received 745 formal assessments requests from families. This was an increase from 626 during the same time period in 2017/18.
"Approximately 70% of the assessments requested were agreed and formal EHC Plans were put in place."
*According to the DfE, the completion rate was 25.1% for the calendar year 2018.
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