In Mahoney v. Carlsbad Unified School District, the 9th circuit court of appeals considered the parents' allegations of procedural violations by the school district under the IDEA. Among the points addressed by the court is the requirement under federal law that an IEP team must include "not less than one special education teacher, or where appropriate, not less than one special education provider of such child." The obvious rationale behind this is to have someone knowledgeable about the student's special education issues and qualified to make recommendations. The parents, whose child had a speech and language impairment, argued that the IEP team was improperly constituted becasue it did not include the child's current special education teacher. Instead, the child's previous speech and language services provider was in attendance. The court rejected the parents' argument stating that federal law does not require that it be the child's current teacher and that it was sufficient to have a provider who had at some point actually taught the student (which, the court determined, the speech provider had).
This case is an example that not every procedural violation will be deemed a denial of FAPE. The violation must be shown to have deprived the parents of meaningful participation in the special education process or interfered with the student's ability to benefit from the educational program. If it were the case that the special education professional had not worked with the child in several years, or the child's needs had changed, or the provider never really understood the child's needs...that would be cause for concern. But here, the court believed that the speech provider had worked wtih the child recently enough and was enough to fulfill the requirements under federal law. Judges and impartial hearing officers can be picky about this type of thing - you have to be able to show more than just a technical error.