AN increasing number of garda files are being deemed as lacking sufficient evidence to warrant a prosecution.
The annual report of the Director of Public Prosecutions reveals that "insufficient evidence" was the reason behind 3,678 cases not proceeding last year.
This represented 79pc of all cases where the DPP decided against prosecution.
The proportion of cases that are dropped for this reason has risen in recent years.
In 2011, some 3,656 cases – 75pc of those dropped – were found to be lacking enough evidence for a prosecution, while 3,514 cases (also 75pc of those dropped) fell into this category in 2010.
Other reasons given by the DPP for not bringing prosecutions last year were that certain cases were not deemed to be in the public interest (113 cases), time limits had expired (37), there had been undue delay (36) and injured parties withdrew their complaints (192).
One case was also dropped last year on "sympathetic grounds" and 72 were dealt with under the juvenile diversion programme, while 137 ended in an adult caution, rather than a prosecution.
The report showed that in almost half of all cases, a decision on whether or not to prosecute was taken within a fortnight of a garda file being received.
A decision in one in six cases is made within two to four weeks, while a quarter of cases are decided upon in one to three months.
Some 8pc of cases took up to six months for a decision, while 3pc of cases took between six and 12 months to decide upon.
Less than 1pc of cases required over a year for a decision on a whether a prosecution would be mounted.