TULSA, Oklahoma - Tulsa County jail is overcrowded and has hundreds of inmates who, according to the sheriff, probably shouldn't be there because of mental illness.

That's why the sheriff wants to add mental health beds at the jail.

The Tulsa County jail isn't big enough to handle all the people who get arrested, but the most urgent part of the problem is the growing number of young inmates, under 18, and those with mental illness.

They have to be kept out of the general population and in a crowded place, that's a real problem.

The county wants to add on to the jail, opening up space for just over 200 more people.

15 years after it was designed, the Tulsa County Jail is now chronically overcrowded.

Prisoners spend many nights on cots waiting for their day in court.

The jail has 2,500 inmates but just 1,700 beds. And the open design makes it difficult to separate regular inmates from the mentally ill.

That's a fast growing category of inmates and according to the sheriff the jail has a difficult time dealing with them.

Sheriff Stanley Glanz with the Tulsa County Sheriff's office said, "We have over 400 people today on psychotropic drugs who need to be in a mental institution or get some kind of healthcare for them."

Earlier in January, the sheriff, some judges and other elected officials called for an expansion of the jail, spurred in part by a grand jury report that documented the situation.

Read the grand jury report here.

District Attorney Time Harris said, "Costs and workload are increasing, particularly in the area of mental health."

Over the first six months of 2013, the jail had more than 6,400 inmates with mental issues and more than 4,300 inmates on psychiatric medications.

They're handled through the regular medical clinic at the jail, and while the sheriff says some need to be behind bars, more just need better health care.

Glanz said there are some who need to be in jail that are violent, but there are others, in the jail, who need to be in mental institutions.

The sheriff wants to build four new pods onto the jail, at a cost of $9 million.

It would take a sales tax extension to do it, and they're hoping to build public support for that through some public meetings over the next couple of weeks.