A dog bit a policewoman as she tracked down its owner for letting it off its leash, a court heard.

Digby, a bearded collie, had already snapped at the thigh of retired Christa Porter as she walked through Eastergate Playing Field, Barnham, near Bognor, on December 1, last year.

Kirsten Sharp, prosecuting at Worthing Magistrates' Court, yesterday, said PC Christine Finch investigated the incident and was attacked as she went to the home of Digby's owner, Lisa Crinion, 32, of North End Road, Yapton, near Arundel.

Crinion was accused of failing to control a dangerous dog and was summonsed to court to show cause why Digby should not be destroyed.

Miss Sharp said: "Ms Porter was walking in the playing fields when a dog bounded up and bit her.

"Digby was chased by Crinion and put back on a lead. The animal was clearly out of control.

"Crinion was found through the identification number on her vehicle.

"Unfortunately, PC Finch went to her house, found the door open and the dog came out and bit her on the leg.

"In police interview, Crinion said the dog is a bit snappy and is likely to nip people."

PC Finch suffered two small puncture wounds and some bruising. Ms Porter suffered bruising to her leg.

In mitigation, Maria Higgins said mother-of-two Crinion, an administrative clerk, had let Digby off the lead because the weather was poor and she did not expect anyone to be in the park.

Insisting there was no need for Digby to be destroyed, Miss Higgins said: "Ms Porter was nipped from behind but the dog's teeth did not go into the leg but into the trousers.

"My client has got two children, aged one and three, and the dog does not behave in this manner at all at home.It is very protective of them.

"The dog is extremely nervous - it is a rescue dog and was ill-treated.

"My client took it in three years ago and has been looking after it. This is the first incident of this nature."

Miss Higgins said Digby would normally be put on a lead when someone visited Crinion's house but a babysitter had forgotten to do so when PC Finch called.

Crinion was ordered to ensure the dog and the babysitter were trained. She also had to keep Digby under control.